description

The SD6834 is a built-in high voltage MOSFET external sampling resistor for switching power supplies Of the current mode PWM + PFM controller series products.

The circuit standby power consumption is low, the starting current is low. In standby mode, the circuit enters Hiccup mode, thereby effectively reducing the standby power consumption of the circuit.

The switching center frequency of the circuit is 25 ~ 67KHz, depending on the load. Jittery Off the frequency, can get lower EMI.

Built-in peak current compensation circuit, can make different AC voltage input when the limit peak Value current consistent. On power-up, the peak current compensation is maximum and then gradually reaches equilibrium, Can reduce the stress in the transformer during power-on, to prevent the transformer saturation. is acceptable Adjusts the peak current through the CS terminal.

The circuit integrates various abnormal state protection functions. Including undervoltage lockout, too Pressure protection, overload protection, pulse leading edge blanking, the original coil overcurrent protection and temperature protection Features. After the circuit is protected, the circuit can be automatically restarted until the system Normal so far.

main feature

* Energy Star 2.0 standard

* Low start current (3μA)

* The switching frequency with the load can increase efficiency

* Jitter switching frequency can reduce EMI

* Overvoltage, the original coil over-current, overload, over-temperature protection

* External peak current sampling resistor

* Undervoltage lockout

* Internal integrated high voltage MOSFET

* Automatic restart

* Peak current compensation circuit

* Initialize the peak current maximum compensation, to achieve soft start function

* Hiccup mode

* Cycle-by-cycle current limit